mocp 2.4.1 don't sound when jackd -d oss

I'm enjoying mocp.
But when I tried "jackd -d oss" and
"mocp -R jack", mocp didn't not sounded.
After I quited the mocp,
I saw following message:
$ mocp -R jack
Running the server...
Trying JACK...
alsa_pcm:playback_1 is not a valid Jack Client / Portalsa_pcm:playback_2 is not a valid Jack Client / Port
I tried xine-jack and MPlayer,
but they sounded well.
Because of above message,I thinked mocp tried connecting to alsa driver,
then I installed alsa-driver,"jackd -d alsa",
and mocp -R jack, It sounded but noisy.

So, I want to use jack and oss,please tell
me how to.

oss sound driver: via82cxxx_audio
jack audio connection kit:0.102.20-1

xine-jack -> xmms-jack (Output plugin)

Try change:
# Jack output settings
JackOutLeft = "alsa_pcm:playback_1"
JackOutRight = "alsa_pcm:playback_2"

to "localhost:jack_port" or somethink simillar in your config file.
(where jack_port is number)

Thank you.
I don't know reflect config file to source, I directly rewrote options.c.
As following:
option_add_str ("JackOutLeft", "oss:playback_1");
option_add_str ("JackOutRight", "oss:playback_2");
Then, mocp didn't show error message.
I cannot confirm whether sound or not because I am in remote login now,
but I believe it goes well.